Maybe it's just because it's the most well-known and familiar setups when it comes to a drum kit...from a historical aspect. No matter what I do I can't seem to be comfortable unless I'm running a 4pc...there's just something magical about it.

I agree! 4-piece kits are magical.

I just can't go back to a three-tom, 5-piece kit anymore. whenever I try, I just can't shake the feeling that I have one tom too many, and end up only using the high rack tom and the floor tom.

I don't know... there's something about a 4-piece that just feels right to me. and for some reason, having more cymbals than drums also feels right to me... besides the standard hi-hats, crash, and ride, I also use a splash and a chinese. (my kit is like Tom Sawyer's kit, but with the splash on the hi-hat side instead of by the ride)

P.S. I'll post pics of my kit in this thread when I get my new cymbals after the holidays.